This passage has an important point to make for both unbelievers and believers respectively.
Regarding unbelievers, the author, the Apostle Paul, makes clear that their thinking is, well . . . , a little bit . . . well, actually quite a bit . . . off. Unbelievers live in “the futility of their thinking.” Paul goes so far as to claim that unbelievers are dullards who have given themselves completely to a sensuality characterized by indulgence, impurity, and lust. Isn’t this a bit extreme? Answer: Michael Jackson, Lifestyles of the Rich and Famous, Playboy, Madonna, Prince, Entertainment Tonight . . . I find such language bracingly refreshing.
Regarding believers, Paul notes that we have new selves that are breaking forth from within the husks of our old selves. These new selves were created so that we could “be like God in true righteousness and holiness.” Paul then makes the implication explicit: “Therefore each of you must put off falsehood and speak truthfully to his neighbor.”
The Greek word translated “falsehood” here is pseudos, which is often used with reference to religious falsehood. The Greek word used here for “neighbor” is plasion, which often carries the connotation of “fellow believer” versus merely “neighbor”. Putting these two observations together, one way to put this into our vernacular might be to say, “Don’t fake it in church.” What if our churches were safe and intimate places where we could honestly wrestle with the husks of our old selves while encouraging one another to put on our new selves in a manner “worthy of the calling we have received” (Eph. 4:1)?
Here is a simple way you can help make it happen. Find two other believers with whom you can start what is called a “Life Transformation Group”. For more information, see the references to Neil Cole and Life Transformation Groups here: http://www.organicchurchplanting.org/resources/allproducts.asp